The present invention relates to an electronic timepiece circuit.
Recently, a proposal has been made in which a clock circuit is assembled into an electronic apparatus such as an electronic cash register or an electronic calculator and data is processed with respect to time. In general, the clock circuit is constructed by an oscillator, a frequency-divider which frequency-divides the output signal from the oscillator to form a "one second" signal and time count circuits for producing "second", "minute" and "hour" signal through counting the "one second" signal. In this type electronic apparatus, when clock data is transferred from the clock circuit to the apparatus main circuit, it is temporarily stored in a memory and then is transferred from the memory to the main circuit. The electronic apparatus as just mentioned has alarm and timer functions in order to more effectively use the clock from the clock circuit. For example, in an electronic cash register, the clock data is used to inform operators of a changing time or to collect data thus far registered at a previously set time for the purpose of effecting the supervising by time. Conventionally, write and read of data to and from the memory and various controls of the clock circuit are carried out by using a microprogram previously stored in ROM (read only memory) in the order of the control. For this reason, when the performance of the electronic apparatus is improved, the microprogram is correspondingly complicated and thus a burden on the software is severe. The time setting data for making an alarm also is preset in the memory. When the time setting data compares with the clock data, both data must simultaneously be read out from the memory. If a plurality of the time setting data are used, the clock data must be read out for each comparing of the time setting data so that the control manner is complex and the total time taken for all the time setting data to be compared is elongated. In the electronic apparatus with the clock circuit, even if the power source to the main circuit of the apparatus is turned off, it should be avoided that the power source to the clock circuit is turned off. For this, the conventional apparatus is provided with individual power sources for the clock circuit. This also requires a circuit construction with less power consumption for the clock circuit.
Accordingly, an object of the invention is to provide a clock circuit well adapted for an electronic timepiece apparatus.